Add a contributors section

[Gulluth]

I would like to add a section to list contributors to the SRD. It does not matter if those contributions are large, such as a complete language translation, or minor such as a fix to formatting, contributors should be recognized for their contributions.

Adding this content to the acknowledgements.md document could be the right place for it, but maybe a dedicated contributors.md is better? I don't know right now and want to discuss.

When the location is identified, the footer section ' user contributions' needs to be updated to link to the anchor or document listing the contributors.